A phase I trial of CEA peptide-pulsed dendritic cells for patients who are HLA-A2 (+) and CEA with breast and GI cancer ---> the endpoints are toxicity and tolerability and immune responses to two infusions of a DC vaccine. We'll also monitor clinical responses in patients with measurable disease. Patients will have leucopheresis before and after dC infusion for archiving of cells for immune assays, and receive esclating doses of autologous dc intravenously to define an MTD in this trial.